Digital BW, The Print

Tom,

You wrote:

>I've never seen anything that stated that greater than 360 dpi would
>produce better output, but I have seen claims that the Piezo driver
>either printed at 2100-2200 on an 1160.


These are two different sets of numbers.  The 360 dpi is the image file at
printing size.  I use 360 dpi as my standard.  That is, in Photoshop I like
my files to be 360 dpi when they are at the size I intend to print.  Some do
say that they can see a difference in 720 dpi files.  I've tried both and
doubt most people can detect the differences at all.

The higher "resolution" that you see -- 720x1440, or Piezo's "2160" --
refers to the dot pattern being laid down.  These printers are actually only
able to print about 10 line pairs/mm in terms of visual information.  That
could be done with 500 dots per inch.  As a practical matter the printers
have about hit the wall at 7.2 lp/mm.  That is the maximum resolution of a
360 dpi image file at printing size.  That is why I don't bother with larger
files.  But I do print at 1440 because it give smoother output.

>I can tell you that when Piezo isn't clogging the print head, it
>really produces some smooth toned images...

That is, in part, due to the high, 2160 "resolution," and also due to the
fact that it is partitioning inks -- putting only the lightest inks in the
highlights.

Interestingly, the VM-Sepia-Neutral that I'm working on is a bit smoother at
5% than Piezo in my 1160 when the neutral curve is used.  This inkset has a
neutral base ink.  Thus, the "neutral" curve withholds all toner in the
highlights.  As such, it is just the light gray in the 5% patch.  This might
indicate that the partitioning of the inks is the major source of Piezo
smoothness, not the 2160 dot pattern.

>Unfortunately, it clogs a lot.

I'm trying to figure out why and have several theories.

> I just ordered some MIS FS ink to try that on the 1160 with the
>Piezo driver (a real advantage is that the Piezo driver prints in
>about 1/3 the time of the Epson driver).

Really, on the 3000 I hear the latest Piezo driver is very slow.

I know many like the Piezo driver.  That is why I'll have ink formulas for
both the VM and Piezo workflows.  I would guess MIS will produce those that
appear to be highly demanded.

Paul
http://www.PaulRoark.com